Cap for armor-piercing projectiles.



R. Al HADFIELD, A. MaK. JACK & A. B. H. CLERKE. CAP FOR ARMOR PIERCING PROJBGTILBS.

APPLICATION FILED MAR. 17, 1913.

1,@76, 419 v Patented 0015.21, 1913.

2 B'HEETS-SHEET l.

R. A. HADFIBLD, A. MaK. JACK a A. B. H. GLERKE.

GAP FOR AARMOR PIERCING PROJEGTILBS. APPLICATION FILED MAR. 17, .1913.

1,976,419. Pafmed o0t;21,1913.

2 SHEBTS-SHEET 2.

tra sraalasrnnr orticanonnen Aneotrr HAJJEIELD, QE WESTMINSTER, AND ALEXANDER, inclinata@ JACK AND AUGUSTUS Bflx QL'l- CIIEBE@ QF SHEFEILEf-D; ENGLAND,

- CAE 310.13. ARMQ3-EIECLNG PROJECTILE sgeciacaaon of Lettere. raient. appunti@ mea-name 1.7, una. stanno. masas.

raten-tea ont. ai, isis.

To all 'whom it may concern Be it known that we, ROBERT ABBOTT Haumann, knight, F. R. S., ALEXANDER McKenzie Jaoinvand AUGUSTUS Basri. Hora` .QLERKEJ subjects of the King of Great Brit- Ynd Ireland, residing, respectively, at

amp? Ca l on House Terrace, in the city of Westminster, England; Brinclitfe, Shei'lield, in the county of .Yo-rk, England, and Hecla lVorks, Sheffield, in the county of York,

England, have invented Improvements in or Relating to Caps for Armor-Piercing Pro-- Inonly used, strikes obliquely against a hard faced armor plate, the inet-al of the cap lwhich lies on that side of the point of the projectile which forms an acute angle with the plate has to be displaced in a radial direction more rapidly than the metal of the cap which lies on the side which forms an 'I obtuse angle with the plate with the result that the lateral or radial pressureexerted by the cap upon the pointed end portion of the I projectile, due to the 'inertia of the Inass of cap metal, is considerably increased on the side nearest to the plate, that is to say on. the side forming an acute angle with the plate, as compared. with that on the other u side of the projectilel'gjthat is to say the sidel forming an obtuse angle with the plate, thus causing an. unbalanced lateral or transverse stress on the pointed end portion of the projectile in addition to the stress exerted thereon" when the point of the projectile reaches the plate with the result that the projectile seldom or never completely perorates the plate without being. itself broken up, except at comparatively high velocities. v

The present invention as for its object to rovide caps adapted to aord amore uniorm and ediective support to the pointed end portion of a projectilethanheretofore whenstriking a hard faced armor plate obliquely, so that the projectile maycornletely perforate the plate without becoming broken up, even when traveling 'at a comparatively low velocity'.l For this purpose the forwardiend; portion of a cap for an armor piercing projectile is so constructed and arranged in relation to the rear portion of the cap, that on its striking an armor plate obliquely, it, or some of it, will, with.-

`portion .of the projectile that''f'ornis an obout unduly'disturljina the rear portion of' the cap, be in the rsy place, thrown over or displaced to that `side of the pointed end tuse angle with the armor plate in such manner that the .mass of cap metal on that sidefis increased so that during the subsequent progression of the pointed end of the projectile through the mass of cap metal, the lateral or radial pressure exerted by. the capy on that side of the projectile, due to inertia of the cap metal, shall be rendered equal or more nearly equal, than heretofore, .to the lateral pressure exerted by the capfon the opposite or acute -side of the pointed endvportion of the projectile'and due to the inertia of the cap metal on that side.

A cap according to the invention is produced by forming it with an annular groove or recess, it may forexample be of V shape in cross section, arranged, between its for- 'wardl end portion, which may be variously shaped, and its rear portion.

ln the accompanying drawings, Figure 1 shows, in longitudinal section, a solid cap constructed accordingto the present invention applied to the pointed'ogival end'por- Jtion of an armor .piercing shell which is shown in elevation. Figs. 2 and' are similar views to Fig. 1 showing two stages of how the forward 'end portion of the cap illustrated in Fig. 1 is thrown over or dis'- placedas described,- on -striking van armor plate obliquely. Fig. 4 is a si'inilar view to, Fig. 1I showing a slightly modified construction of the cap. v v ln the example shown in Fig. il, the cap a, which externally .is mainly of ogival shape with a solid forward end portion a1 having i" a rounded or convex front surface a2, has

formed therein an annular groove b of V shape the inner end or bottom of which surrounds a solid portion c of 'the cap metal of reduced cross .sectional area located ina plane :v transverse to the axis of the-cap which planepasses through or closely adj acent to the point Z 'of the projectile e.'

Figs. 2 and 3 show approximately how the head portion L1 vof thecap on'lstriliirfgf anarmor plate,- displaced to that side l of theY pointed enql portion of the projectile e that forms an b, tuse langle with thevplate. f

The cap shown `in F ig; Il is similar to that, shown in Fig. 1 except that the head portion;

indicated at f, obliquelys.1o5`

' a1 thereof is of smaller radius and diameter and of vles`s axial thickness than that of the cap shown in Fig. 1. 4

It is to be understood .that the invention is not limited tothe eXact disposition mentioned of the groove b, as the sameV may be arranged a little more forward, or to the -radiusof curvature shown of the head-por@ tion al bfeither of the capsillustrated, but

good results have been obtained with caps.l constructed as shown in Figs. 1 and 4.

1) to present a continuous surface to the air during flight. Or the cap may, if desired, be surmounted by a hollow air deiector of known or "suitable construction and such for example 'as .is described in the specication of former. British Letters Patent No.16901 Yof 1898 granted to one ofus, or in the specilication of former British Letters Patent No. 2,817 of 1908, granted to-two of us. Such a cap will inclose the solid forward'end portion al of the cap and be secured to the body or rea'rportion Z) of thecap. Usually however; caps constructed as described and made offthe shape shown will not need an air de.

Hector. The use of 4sheet covering material for the groove b, or of an. air deiector, is not however in any wayessential for attaining.'

the object. ,of this invention and such use ,forms no part of this invention and no claim is made thereto.

What We claim* is 1. A cap, for an armor piercing projectile, having an annular' groove or recess formed therein between its solid front end orhead portion and its rear or body portion.

2. A cap, 'for an armor piercing projectile, i

having an annular groove or recess of V shape 1n cross section formed therein between its solid front" nd or head portion and its rear 'or body portion.

3. A cap, for a pointed armor piercing projectile, made externally mainly of ogival. shape with a solid front end portion and having therein an annular groove between. its front and rear portions.

' 4; A cap, fora pointed ar'mor piercing 55 projectile, made eXternally-mainly of ogival shape witha solid front end or headvpor- Vtion having ar'rounded or Aconvex `front surface and having an annular groove or recess' therein between its frontend lor head' por- `60'.

tion and its rear or body portion.

5. A cap, for a pointed armor piercing projectile, having an annular groove or'recess formed therein between its solid front end or head portion and v`its rear or body portion and surrounding a solid connectingA port-ion of the cap metal of reduced cross section located in a plane that is transverse to the axis of the'cap and is adjacent to the f point of the cavity in the cap designed'to it- 70A the pointed end of a projectile.

6. -A cap comprising a rear or body portion adapted` to fit a pointed armor piercing projectile and-a forward end or head pory tion connect-ed to the rear or body portion by intervening Icap-I metal of reduced cross sectional area arranged to leave a 'space between the adjacent outer parts of the said two portions of the cap that will allow of the front end or head portion moving laterally relatively tothe rear orbodyortion on `its striking an obj ect obliquely, su stantially as described for thepurpose set forth.

Signed at Sheffield, England this twentieth day of February 1913.

ROBERT ABBOTT HADFIELD.

ALEXANDER MKENZE, JACK.

4 AUGUSTUS BASIL lOLT CLERKE.

Witnesses:

PHILIPP ADAM MEHL, L. F. KAYE, I ERNEST Romans, LEONARD BOWLAND.

Copies of this patent may be obtained for ve cents each, by addressing the Gomm'is'vsioner of Patents.

' Washington, D. C. L 

